Hence, the pathological mechanisms do not necessarily require a mutation in the protein sequence to trigger aggregation.
While this approach has the advantage of enabling disruption at will of a single or more bromodomains, it requires a mutation to be introduced into the target protein.
In particular, results demonstrated that many known oncogenes consistently harbor mutations at relatively few specific amino acid positions, suggesting that oncogenic activity does not result from random mutation(s) in an oncogene, but rather requires a mutation in one of a few locations.
In each subset, we required a minimum mutation frequency of 5%.
Rodent cells required a single oncogenic mutation coupled with abrogation of the major cell cycle checkpoint regulator p53, while human cells required the addition of multiple oncogenic mutations targeting several intracellular pathways critical to cell cycle progression and survival, which include p53, pRb, and the Ras/MAPK pathway as well as cellular phosphatases [ 3].
The results for the four cases below are presented in terms of two key model outputs: (1) relative tumorigenic efficiency of mutator vs. non-mutator pathways, Nrel, and (2) the minimum fold increase in mutation rate required from a mutator mutation before the mutator pathway has a relative tumorigenic efficiency greater than or equal to 1, termed α50%.
However, whereas resistance to NVP requires a single mutation, resistance to ZDV requires multiple sequential mutations.
A specific single-point mutation in either of these genes confers low-level resistance, with high-level resistance generally requiring a point mutation in both gyrA and parC QRDRs.
Analysis of the DNA sequences for H3F3A and H3F3B illuminates why the K27M mutation is restricted to H3F3A, as K27 is coded by AAG in H3F3A and by AAA in H3F3B, requiring a single mutation in H3F3A to generate ATG to code for methionine (Fig. 3).
The amount of DNA required for a mutation analysis can be of importance when analysing minimal colonoscopy fragments or core needle biopsies.
